Room air conditioner



Oct. 29, 1957 LATHROP 2,811,022

ROOM AIR CONDITIONER Filed Nov. 15, 1953 4 Sheets-Sheet. 1

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Oct. 29, 1957 H. F. LATHROP 2,811,022

ROOM AIR counrrxomsa Filed Nov. 13, 1953 4 Sheets-Sheet 2 Z .4 qHZ 3 1571 5 TlZUT Hara/a F Lazi zro o b he an; g%dyifm Oct. 29, 1957 F. LATHROP 2,811,022

ROOM AIR CONDITIONER Filed Nov. 13. 1953 4 Sheets-Sheet 3 DRY (001.

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ROOM AIR CONDITIONER mm Nov. 13. 1953 4 Sheets-Sheet 4 Ham/a Lazlzro o- Unite States ROOM AIR coNnrrroNER Application November 13, 1953, Serial No. 391,863 18 Claims. (Cl. 62-129) The present invention relates to air conditioning equipment, and more particularly is concerned with the provision of a novel and more effective apparatus for controlling the various interrelated motors and air flow dampers thereof.

With the advent of widespread ownership of air conditioning units, and especially of the type which is positioned in a room window for conditioning a single room, the need for improved controls has increased. In view of the fact that air conditioners of this type are positioned for ready adjustment by the user, and further in view of the fact that many of the users are women or other persons unskilled in the operation of mechanical devices, it has been desired that a control system be provided which is capable of operation through a single, simple, control lever.

I am of course aware of the fact that interrelated controls have been used in the prior art of air conditioning. However, to my knowledge, the prior art control structures have been limited to rotary type control levers and have failed to provide the completeness of control available in the simplified, reciprocating, structure herein provided.

In order to provide a control system which is extremely rugged, compact, and simple to operate, the present invention utilizes a pair of oppositely reciprocatable control rods for actuating fresh air and room air exhaust dampers, a directly actuated room air recirculation damper at the inlet to the refrigeration evaporator and a multiple position rotary switch capable of actuation simultaneously with the reciprocation of the damper controls for selectively energizing the refrigerant compressor motor, the fan motor, or an electric heater, or a combination thereof, as may be desired. By operatively associating theswitch or energizing means, with the reciprocating controls, the control system herein shown provides a complete range of operation for winter or summer use by means of a single reciprocating knob having a plurality of positions along a horizontally disposed dial.

It is, therefore, an object of the present invention to provide a novel master control system for air conditioning apparatus.

A further object of the present invention is to provide a simplified master control system for air conditioning units while at the same time providing a substantially rigidified structure.

Yet a further object of the present invention is to provide an automatically interrelated damper control system for room air conditioners in which dampers controlling fresh air inlet, room air exhaust, or room air recirculation may be controlled and proportioned by means of a single sliding lever.

A feature of the present invention is the interrelationship of a pair of reciprocating transmitting cables having lost motion in opposite directions.

Another feature of the present invention is the provision of a reciprocating control platform which alternatively actuates one or the other of a pair of reciprocating atent transmission cables and simultaneously actuates a recirculation damper in a positively driven manner.

Another object of the present invention is to provide a rotary control switch for the interrelated energization of an air conditioner motor and fan, which switch is actuated in a predetermined relationship with the air distribution dampers of the conditioning unit.

Another object of the present invention is to provide a novel air distribution damper arrangement for distributing air from the evaporator chamber of the air conditioner to the room.

A further object of the present invention is to provide an interrelated damper control system for proportioning a desired amount of fresh air with recirculated air at the inlet to the evaporator of an air conditioning unit.

Another feature of the present invention is the interrelationship of an inlet damper controlling the flow of room air to the evaporator chamber of an air conditioning unit to reduce the air flow to said evaporator and thereby increase the dehumidification of recirculated air.

Yet another feature of the invention is a full length room air recirculation control damper positioned upstream in the air flow to the evaporator chamber whereby the condensation of moisture from the air by the evaporator may be varied. V V

Still other and further objects and features of the pres: ent invention will at once become apparent to those skilled in the art from a consideration of the attached drawings which illustrate a preferred embodiment of the present invention and in which: i I v Figure 1 is a front elevational view of an air conditioning unit constructed according to the present invention and illustrating my control panel;

Figure 2 is a plan view in cross-section taken along the line lIIIof Figure 3;

Figure 3 is a partial, side elevational view in cross-section taken along the line IIIIII of Figure 1;

Figure 4 is a cross-sectional'view taken along the line IVIV of Figure 3 and illustrating the positioning of the recirculation damper;

Figure 5 is a plan view in cross-section taken along the line VV of Figure 3 but showing the controls in the extreme left hand operating position;

Figure 6 is a plan view in cross-section taken alongthe line VV of Figure 3 but having the parts in the extreme right hand operating position as viewed in Figure 1;

Figure 7 is a schematic view illustrating the electrical connections forming a portion of the present control system.

As shown on the drawings:

As may be seen from a consideration of Figures 1 and 2, the control apparatus of the present invention is utilized in a generally rectangularly shaped air conditioning unit positioned in an opening in the wall of a room to be air conditioned. The conditioning unit comprises an outer housng 10 which is preferably semi-permanently secured in the window opening 11 by any conventional mounting means. The housing 10 is preferably constructed of sheet metal and is adapted to cover the sides and top of the air conditioning apparatus and, further, is constructed to provide supporting means 12 along its lower edges for supporting a base pan 13.

The base pan 13 is preferably of conventional design and is provided with an upstanding peripheral flange, thereby making it dish-shaped for the collection of con densate. A condenser 14 and an evaporator 15 are secured to the base pan 13 at opposite ends thereof and are separated from each other by an intermediate insulated partition 16 thereby providing an evaporator compartment and a condenser compartment. The ends of the sheet metal housing 10 are open, and hence'the condenser 14 faces outdoor atmosphere while the evaporator 15 faces into the room. Thus, the condenser compartment is open to air flow from the outside and the evaporator compartment is open to air flow from Within the room.

The conventional refrigeration compressor 17 is provided in the condenser compartment and a fan motor 18 is mounted in the condenser chamber, preferably by securing it to the partition 16 or the base pan 13. The fan motor 18 carries a condenser fan 19 which moves air inwardly through the condenser 14, over the motor 18 and the compressor 17. The motor also drives a centrifugal fan 20 which draws air through the filter 21, through the evaporator into the lower chamber 22 through the centrifugal fan which forces the air upwardly through the overhead outlet chamber 2 3 past the outlet grill 24 into the room. a

The above described air circulatory paths are those defined by the enclosure walls 10 and 16 without regard to modification of the air flow resulting from damper controls. "The 'air'conditioning unitoperating under the above described airflow would provide what is generally termed -recirculation of the room air with cooling and dehumidification only. No provision is made, in the above described air flow for either exhausting stale air from the room or for the introduction of fresh-air into the room'from the outside. Also, no controls are provided for varying the rate of flow over the evaporator apparatus, and as a result, a constant rate of dehumidification is provided.

While the above outlined apparatus provides a large amount of refrigeration, it has been found inadequate in most homes since it is usually desired that fresh, filtered air 'beavailable from the outside and also that room air be exhausted or heated on occasion. Further, it'is often desired to increase the rate of dehumidification of the air Within the room. Additional controls for accomplishing these functions are provided by the present invention and are correlated with each other so that the positioning of asingle control knob will automatically provide different types and varying degrees of refrigeration or heating.

As may ditioner of correlated be seen from Figures 2, 5 and 6 the air conthe present invention is provided with three air control dampers, namely a fresh air damper 27, an exhaust damper 28 and a recirculationair damper 29. A consideration of the air pressures resulting from operation of the fans 19 and 20 indicates that the condenser compartment will be under a positive pressure caused by theoperation of the fan 19 to draw outside air into the condenser compartment, while the lower'evaporator compartment 22 is under a reduced pressure since it provides the source for the fan 20. The high pressure chamber 25, which constitutes the exhaust or high pressure side of the centrifugal fan 20 is in direct connection with the outlet chamber 23 as may be seen from Figure 3.

From the above, it will be apparent that the condenser chamber and -the chamber 25, which lie on opposite sides ofthe'right hand portion of the separating wall 16 as viewed in Figure 2 will be under a positive pressure. However, dueto the design of the fans 19 and 20, the pressure built up in the chamber 25 will be of a substantially greater degree. Thus, While fans 19 and 20 are in effect pumping against each other,'air will flow in an exhausting direction through the partition 16 when the exhaust damper 28 is On the other hand, when the fresh air vent damper 27-is in its open position, shown in Figure 6, the positive pressure found in the condenser compartment as aresult of the fan :19, coupled with the reduced pressure found in the chamber 22, will cause astrong flow of outside air through the damper opening 27, through the side channel 30, around the end wall 31 of the chamber 22, through the filter 21, the evaporator 15 and out through thefan 20 to the exhaust chamber 23 and from thenceto the'room.

open.

.21, theevaporator'15 and on through the 29.

By passing all of the fresh air entering through the vent 27 over the filter 21 and the evaporator 15 prior to releasing it from the air conditioning cabinet enclosure, all of the fresh air will be filtered and cooled before entry into the conditioned space. Further, even if the compressor is not in operation, all of the fresh air entering the air conditioning cabinet evaporator chamber through the damper 27 will be filtered prior to its distribution to the room. This is of course, an important matter in industrial areas where ventilation is practically impossible without filtering the air being brought in from the outside atmosphere.

Recirculation of room air through the evaporator 15 is accomplished through the room air inlet 35 in the bottom of the front cover 36. This opening is controlled by means of the damper 29 which comprises a rectangular sheet of material pivoted about the rod 37 to the side walls 22a and 22b of the main evaporator enclosure as may be seen from Figures 2, 4, 5, and 6. The damper 29 is provided with an upstanding cam extension 38, which is preferably integral with the damper portion 29 but may, of course, be constructed of sheet metal or deformed bar stock'rigidly secured to the damper 29 by any conventional means.- In either construction, the cam surface is arranged to follow a line composed of points lying a constantdistance from the pivot 37 but positioned on radius lines lying at varying angles to the plane of the damper 29.

As may be seen from Figure 3, when the damper 29 is positioned in the dotted line position 2% adjacent the filter 21, the air flow through the opening 35 is effectively blocked from passing through the filter to the evaporator 22 and through the fan 20.

It is to be noted however, that the damper 29 in no way interferes with the passage of fresh air from the vent 27, through the side channel 30 and from thence through the filter 21and the evaporator 15. This is true since the chamber 30. extends from the base pan 13 upwardly the entire height of the filter 21 and the evaporator 15. Thus, air passing through thc passage 30 may fiow behind the damper 29 very readily, even though it is in the closed, or dotted line position shown in Figure 3. It is tl us evident that the damper; 29 and the damper 27 may be controlled to provide selectively, fresh air from the outside, or recirculated air from the room, or varyingproportions of the two, to the evaporator 15, upon the: utilization of interrelated controls. Of course, it is to 'beunderstood that when the damper 29 is positioned init h e solid line position indicated in Figure 3, air will pass-directlythrough the aperture 35 through the filter evaporator fan i Having thus described the positioning of the dampers utilized 'fQ1' purposes of air control, the interrelationship pfovidedby the structure of the present invention will now be described. Since the fresh air inlet damper 27 leads fresh air directly to the evaporator fan 20, and since the evaporator-fan 20 pumps air under pressure into the area 25 adjacent the exhaust opening 28, it is clear that in order to provide effective fresh airsupply to the room, the exhaust damper 28 must be in the closed position when the fresh air vent 27 is open. Therefore, apparatus is provided for alternatively opening the dampers 27 and 28. 4 j

The above mentioned alternative operation is provided in the present invention by means of a reciprocating platform 40 which is preferably constructed of sheet metal. Eats 41 'are'turned downwardly from the platform 40 andjare'provided with apertures for the passage of a fixed mounting rod 43. The mounting rod 43 is rigidly secured to the base structure 13 ofthe air conditioning unit,"preferably through amounting bracket 45 which is secured to the bottomclosure wall 46 of the chamber 23 byfmeans of any conventional fastening structure, such as rivets 4 7. In this connection, it is noted that the bottom closure plate 46 provides a cover plate for the evaporator compartment and shrouds the evaporator and filter 21' to prevent air from passing upwardly and over the filter 21 and the evaporator 15 into the fan inlet'chamber 22. The plate 46 may of course be secured to the evaporator 25 or to the walls 22a, 22b whichever is desired. In any event, it is necessary that the rod 43 be firmly fixed relative to the base structure of the air conditioning unit.

The platform 40 is moved laterally along the rod 43 by means of a single actuating knob 50 which is secured to the plate 40 by means of a riveted, or otherwise secured, extension 51 which extends through a slot 52 in the indicator plate 53. As may be seen from a consideration of Figure 1, the slot 52 extends substantially the entire length of the indicator plate 63 and permits the movement of the actuating knob 50 between extreme positions of exhaust and fan-vent. The indicator plate 53 is secured to the fixed support 45, or the hood 36, whichever is preferred and thus remains in a constant position relative to the rod 43.

Actuation of the fresh air and exhaust dampers respectively is accomplished by means of lost motion connections between the plate 40 and the respective dampers 27 and 28. As may be seen from Figures 5 and 6, the plate 40 is provided with a pair of bent over lips 55 and 56 which slidably support the fresh air damper actuating rod 57. The rod 57 carries, at the right end thereofas' viewed in Figures 5 and 6, an abutment washer 58 maintained in position on the rod 57 by means of a cotter key 59 or similar conventional means. A second abutment washer 60 is slidably mounted upon the rod 57 at the left end of a normally uncompressed take-up spring 61.

The car 56 and the washer 60 are constructed so that upon movement of the car 56 t the right, the washer 60 will abut the car 56 and further movement of the car 56 can be accomplished only through compression of the spring 61 or movement of rod 57. The damper 27 is provided with a hinge 62 by which it is pivoted to the portion 16a of the dividing wall 16 and further carries an extension 63 rigidly secured thereto and extending into the path of the bent over arm 57a carried by the actuating rod 57.

In order to prevent undesired rotation of the loosely mounted rod 57, an aperture is provided in the extension 63 and a portion 57b of the arm 57a is positioned in the aperture, thereby preventing the arm 57a from turning about the axis of shaft 57 and into a position out of contact with the damper actuating extension 63.

As may be seen in Figure 5, the shaft 57 is in an inactive, or non-actuated position when the actuating knob 50 is in its extreme left hand position. Sufficient lost motion is provided between the abutment 56 and the washer 60 so that the fresh air damper 27 is not actuated in the counterclockwise direction, or into the open position until the actuating knob 50 has moved to the right, as viewed in Figure l, to the position entitled cool ven In the cool vent position, the damper 27 is in a partially open position intermediate between that shown in Figures and 6.

In opening the damper 27, the spring 65, which normally biases the damper 27 closed, must be overcome in order to provide a smoothly balanced opening operation. The spring 61 is constructed to collapse partially before the damper 27 begins to open. This compound resiliency provides a smooth damper action and also permits sufficient resiliency in the system to prevent possible jamming of the mechanism due to very slight misalignments caused by imperfect assembly. It has been found that the provision of the spring 61 and the washer 60 have substantially eliminated any problems of binding relative to the actuating shaft 57 and as a result, no expensive reaming operations or similar expensive operations or parts are necessary relative to the turned over lips orears' 55 and 56 to provide perfectly alignedbearmgs.

As shown in Figure 6, by movement of the actuating knob 50 to the extreme right hand position, or in other words, into'the position of fan-ventjf the damper 27 is moved into its fully open position thereby admitting the maximum amount of fresh air through the partition 16a to the passageway 30. e 1 I Actuation of the exhaust damper is accomplished in a manner similar tothat above described 'relativeto the fresh air damper 27, except that the exhaust damper is actuated upon movement of the platform 40in the left hand, or opposite direction. The lost motion forthe exhaust damper is provided by means of the ear 67 turned upwardly from the plate 40 in combination with the abutment 68 which is rigidly secured to the actuating cable 69 which is in turn connected at 70 to the exhaust'damper 28. The cable 69 is slidably mounted in the fixed cable housing 71'and movement of the abutment 68 toward the left will caus'e'a pull at 70 upon the damper 28. -The' damper 28 is normally biased into the closed position against the partitionportion 16b by the spring 172 which is confined between the damper 28 and the fixed abutment 73 which carries the cable housing 71. The fixed abutment 73 may, of course, be carried by any portionof the air conditioning apparatus which is secured to the base plate 13, and is, preferably carried by a portion of the closure plate 46 in the compartment 23. I,

Actuation of the damper may be clearly understood from a consideration of Figures 5 and 6. In Figure 6, the actuating knob, and hence the plate 40 are positionedin the extreme right hand, or fan-vent, position. In that position the abutment 68 on the actuating cable 69 is not invcontact with the ear 67 on the plate 40. This istrue since the abutment 68 moves to the right only to the extent necessary in permitting the damper 28 to move to the closed position under the influence of the spring 72. However, upon movement of the actuating knob 50 to- Ward the left, the ear 67 intercepts the abutment 68 and: moves the actuating cable 69 toward the left in opposition to the biasing spring 72. Opening of the damper 28 is desired only in the position of exhaust and hence the abutment 68 is positioned on the cable 69 so that it will be intercepted by the ear 67 at a position only slightly to the right of'the position exhaust on the indicator plate and will be moved to the point of maximum exhaust damper opening at the position immediately adjacent the left hand end of the slot 52.

From the relationships above described, and. shown in Figures 5 and 6, it will be apparent that a range of fresh air damper opening positions will be provided adjacent the right hand end of the indicator plate and arange of exhaust damper open positions will be provided at the left hand end of the damper plate. The extent of these ranges is indicated in Figure 1 wherein the range denoted A is the range of movement of the knob 50 corresponding to movement of the exhaust damper and the range B is the range of movement corresponding to move-f ment of the fresh air damper. i

In view of the resiliency of the fresh air damper hookup, provided by the spring 61, the fresh air damper is permitted to reach its maximum open position ata point C between the cool-ven and the fan-vent positions. From the left end of range B to the point. C, the fresh air damper is gradually opened, permitting a mixture of fresh air with that of the room. From the point C to the right, continued movement of the knob 50 will causev no further opening of the fresh air damper but will maintain the damper in its fully open position.

It is thus apparent, that the exhaust and fresh airdampers are alternatively operated and that an area is pro vided in which neither the fresh air nor exhaust damper is in the open position. Thisintermediate area is utilized as described below for the recirculation and cooling or heating of the room air.

Control of the recirculation of room air is provided by means of the damper 29. As explained above, the damper 29 is provided with a cam surface 38, an end view of which may be seen in Figure 3. The cam surface 38 is more clearly seen in Figure 4 wherein the damper 29 is viewed from above in its wide open, room air recirculation, position. As may there be seen, the cam surface 38 is deflected rearwardly along a portion 38b until it reaches an extreme position 38c in which the cam surface is positioned at an angle D relative to the damper 29. As may be seen from Figures 3 and 4, a straight portion 3811 provides the other extreme cam position and lies at an angle E relative to the damper 29.

The cam surface 38 cooperates with a pair of rollers 75 which are rotatably mounted on the plate 40. Since the support rod 43 and the recirculation damper pivot 37 are positioned on parallel axes, it will be clear that movement of the actuating knob 50 along the rod 43 will cause the rollers 75 to traverse a path directly over and parallel to the pivot 37. Since the cam surface 38 is positioned between the rollers 75, reciprocation of the rollers 75 will cause the damper 29 to be pivoted from a solid line, open, position shown in Figure 3 in which the rollers contact the portion 38a of the cam 38, to a position in which the rollers 75 have moved to the right as viewed in Figure 1 to a position in which they cooperate with the portion 380 of the cam surface 38 to maintain the damper 29 closed. A plan view of the operation of the damper 29 by the rollers 75 may be seen in Figures and 6 wherein the rollers 75 are in contact with the portions 38a and 380 of the cam 38 respectively.

Operation of the fan and compressor motor controls is also accomplished through reciprocation of the platform .40 by the control knob 50. For this purpose, a toothed rack 76 is secured longitudinally along the member 40. As shown in Figure 3, the rack 76 is integral with the sheet metal platform 40 and comprises the bent up flange 77 with the teeth 76 thereon. The flange 77 is in turn deformed from the horizontally projecting flange 78 and the upturned side 79 which carries the ears 55 and 56 associated with the fresh air damper control above described.

A backing roller 80 is rotatably mounted upon a fixed support 45 in contact with the guide flange 78. This arrangement provides support for the platform 40 through the guide flange 78 as well as at the ears 41 riding upon the longitudinally extending rod 43. This three point support prevents the platform 40 from dropping downwardly unto the cam 38 and also maintains the reciprocating control rods 57 and 69 in a bind-free, constant position.

The rack teeth 76 engage a gear 81 securely fixed to the switch shaft 82. The shaft '82 is the operative member of a rotary switch 83 rigidly secured to the fixed housing 45 by means of a conventional center post fastening nut 84. In constructing the apparatus, it is desired that the center post be mounted in a somewhat elongated vertical slot rather than a round hole. Thus, the switch 83, with its shaft 82, may be moved vertically somewhat to provide the desired engagement tension between the gear 81 and the rack teeth 76.

'In assembly, the gear 81 is mounted to fully engage the rack 76 and maintain the guide flange 78 in engagement with the rollers 89. By thus positioning the switch 83, all slack is taken out of the rack support, as well as the supports for the reciprocating damper controls, thereby preventing rattling and other annoying vibrations during operation of the controls. In this connection, it is to be understood that the rollers 75 and 80 may .be of any suitable material, but it is preferred that they be coated with rubber, nylon, or similar resilient material capable of damping.

The control switch 83 may comprise any conventional type of multiple control type switch either of the rotary type or the type comprising a plurality of axially spaced switches actuated by cams on the reciprocating platform 50, but preferably it takes the form shown in Figure 7, There, the shaft 82 carries a conducting wiper 86 which is electrically connected by means of a conductor 87 to source of electricity 88. Current is taken from the wiper 86 by means of a fan control segment 90, a compressor motor segment 91, and a heating coil segment 92. While the switch 83 is a continuous one, seven operative positions are provided, corresponding to the positions in dicated on the control dial panel shown in Figure 1. These positions are indicated by the radially extending center lines of Figure 7 bearing indicia corresponding to those found on the indicator plate.

The fan motor 18 is connected by means of the conductor 93 to the segment 90, and by the return conductor 94 to the source of electricity 88. The segment extends substantially around the periphery of the switch 83 but is provided with an interrupted portion at the off position. In all the remaining positions of the control knob 50, the fan motor 18 is energized.

The compressor 17 is likewise electrically connected to the return 94, and to its segment 91 by means of the connector 95. However, the segment 91 "is relatively short and as may be seen from Figure 7 provides an electrical connection between the wiper 86 and the conductor 95 only when the control knob 59 and hence the wiper 86 is in the cool-vent, dry-cool and cool positions. No cooling effect is provided in the fan-vent, exhaust, heat, or on positions.

Since the compressor 17 is not, for obvious reasons, in operation during the heating season the segment 92 is positioned in a vacant portion of the arc of the segment 91. This placement permits a minimum space requirement of the switch 83 without curtailing the operation in any way. The segment 92 is connected by the conductor 96 to the heater resistance coil 97 which is in turn connected to the return 94. The heater 97 is in operation only during the period when the knob 50, and hence the Wiper 86 is in the heat position.

While no switch position-maintaining detents have been shown, it is contemplated that conventional spring biased detents be provided to maintain the wiper 86 in its selected position. In view of the direct relationship between the switch 83 and the platform 40, it will be understood that the switch detent will also provide the means for maintaining the knob 56 in its various selected positions.

Having thus described the component elements of my interrelated control mechanism, its operation as a unit will now be explained. After installation, and the connection of the unit to an electrical source, control of the fresh air damper, the exhaust damper, the recirculation damper, and the motor switches may all be accomplished through the single master control knob 50. This control may best be described by the discussion of the separate, control knob positions.

Exhaust.In the exhaust position, the control knob 59 is positioned at any desired point within the range A, indicating the exhaust damper opening, and positioned directly under the word Exhaust on the indicator panel. In this position, a plan view which may be seen in Figure 5, the exhaust damper 28 is in its open position and the fresh air damper 27 is closed. Likewise, the rollers 75 are in contact with the portion 38a of the cam 30a and the recirculation damper 29 is therefore also in the open position, permitting maximum .air flow from the room to the air conditioning unit through the aperture 35. Due to rotation of the gear 81 in response to movement of the control knob St to the exhaust position, the wiper 86 is rotated to the angular position marked Exhaust in Figure 7 in which the fan motor 18 alone is energized.

Thus, in the Exhaust position, room air is drawn in through the aperture 35 past the open damper 29, through the filter 21, the evaporator 25, through the fan aims 20, out through the exhaust damper 28 and from thence to the outside atmosphere. As explained above, while the fan 19 provides a positive pressure in the condenser compartment, the fan 20 provides a higher pressure than the fan 19 and hence, air flow isdirected outwardly through the partition 16 and the opening 28.

Heat.During the winter months, the air conditioning unit of the present invention may be utilized for purposes of providing heat to theair of the room. Since it is not desired to heat fresh air directly from outdoors, it being more efficient to heat recirculated air, recirculation damper 29 is maintained in its opened position by contact of the rollers with the section 38a of the cam 38.

Thus, the damper 29 is in the full line position shown in Figure 3. Likewise, it is desired that both the exhaust and fresh air dampers be closed. Therefore, movement to the heat position will cause disengagement between the abutment 68 and the car 67 of the platform 40 and, likewise, the ear 56 will not bein contact with the abutment 60. In view of this, the biasing springs 65 and 72 will maintain the dampers 27 and 28 respectively in their closed positions. In order to circulate the heat generated by the heating element 97,the fan motor 18 is energized at the same time as the element 97. "The electrical connections may be clearly seen from'F-igure 7 wherein, in

the heat position, the right.

Ofi.In the off position, the dampers remain in exactly the same position as inthe heat position above described, with the exhaust and freshQai-r dampers closed and the recirculation damper open. However, no electrical contact whatever is provided between the wiper 86 and any of theelectrical'eomponents 17, 18 or 97. Thus, no air is moved, nor is any electrical energy consumed.

Cool.--In the cool positionjthecontrol knob 50 is positioned directly under theportion marked Cool on the indicator panel andthe controls are positionedas indicated in the solid lines of Figure 2. Thus, the fresh air, exhaust, and recirculation dampers, are in the same positionas indicated above in connection with the heat and off positions. No fresh air is circulated and the entire cooling effect is performed upon recirculated air. In this position, both the compressor 17, and the fan motor 18 are energized and a maximum amount of recirculated air is permitted to pass through the fully open damper 29, through the filter 21, the evaporator 25, the fan 20 and out through the room air chamber 23 to the room; Y

Dry-c 0L-The dry-coolposition is provided in order to, increase the dehumidification of the recirculated air. Thisis'accomplished by partially closing the recirculation damper 29-without modifying the condition of any of the remaining elements. Thus, the rollers 75 move into contact with the cam surface 38b, and proceed along it approximately half the length of that surface. This causes the damper 29 to move into the position indicated by the dotted line 29a as shown in Figure 3, closing off approximately half of the recirculation air opening 35. As may be seen from Figure 7, in the dry-cool position both the compressor and the fans are in energized condition. Further, the fresh air damper control has not yet quite reached the opening position. Thus, the car 56 and the abutment '60 are positioned immediately adjacent each other but are not in force'transmitting position as yet.

Due to the restriction on the air flow to the evaporator through the opening 35, a smaller volume of air is passed over the evaporator 25, thereby more efliciently cooling the recirculated air. This results in the cooling of the recirculated air to a greater extent than that which would occur in the Cool position thereby removing a larger amount of moisture from the air. This air conditioning position is particularly effective in very moist weather in which the humidity level has become the determining factor in comfort. t

the wiper 86 extends horizontally to l C0ol-vent.-In many'cases' it is desirable that 'a por tion of the air cooled and circulated by the air conditioning unit be fresh air from outside the room. The present control system provides for the introduction of fresh air invarying proportions in combination with recirculated, air. This is accomplished by movement of the control knob 52 to the range' indicated at B, in Figure 1. Within that range, the fresh air damper 27 is progressively opened as the knob 50 is moved toward the right in Figure 1. In view of the angular relationship of the cam surface 30b, movement of the knob 50- toward the right also causes continued closingmovement of the damper '29 simultaneously with the opening movement of the fresh air damper 27. Therefore, the control system automatically provides proportioning between recirculated air 'andfresh air such that as the amount of fresh air increases, the amount of room air recirculated-decreases. As may be seen, from Figure 7, the Cool-vent position of the wiper 86 provides an electrical contact between the wiper S6 and the segments 90 and 91, thereby energizing both the compressor 17 and the pan 18. i

Assuming that the knob 50 is substantially directly under the word Cool-vent as viewed in Figure l, the fresh air damper will be substantially one-half way open and the damper 29 will be about three-fourths closed. In this position, fresh air will be drawn in through the damper 27, along the passageway 30, around and through the filter 21 the evaporator 25 to the fan 20. Likewise, a current of air will be drawn through the restricted opening 35, through the filter 21, the evaporator 25 and to the fan 20 which will force both the fresh air and recir culated air which has been filtered and cooled out through the chamber 23 to the room. 'As has already been explained above, movement of the recirculation damper 29-to a closed position does not block off or provide any restriction of the air flow from the passage 30"to the evaporator, since that'passage extends above'the' axis of rotation of the .damper'29. f

Fart-vent.-As the" control knob 50 -is'rriove'd' toward: the right from the Cool-ventto the Fan vent position, 'the' fresh air damper is moved to ,thefully openposition, as.

7 shown in the solid lines of Figure 6. In'th'is position, the

exhaust damper is closed and outside air is ,forcedint'o the evaporator chamber under 'afslight positive pre's'sure resulting from the operation of fari'19l Thus,' air hows through the damper 27, into the chamber 30, around the filter 21, through the evaporator 15 the fan 20 and out into the room through the chamber 23. In view of the positioning of the filter 21, it is apparent that the fresh air which is admitted through the damper 27 will be filtered prior to its distribution to the room, thereby preventing the ingress of dirt and other undesirable material from the outside atmosphere. As-may be seen from: Figure 7, the compressor 17 is not energized in the Fanvent position thereby preventing any cooling effect.

While the above outlined control system provides a simple and extremely rugged apparatus capable of providing varied control of fresh air room exhaust, recircu lation, cooling and heating it is also desired that a con-v trol be placed over the direction of air flow from the chamber 23. This may be provided through an inde-. pendently operated damper which is'pivoted about a support rod 101. The rod 101 is' preferably secured at its ends to the end faces of the enclosure hood 36 and is positioned at the upper corner thereof. Vertically extending, parallel, slots are provided in the sides 102 and 103 of the hood 36 through which air leaving the-chamber 23 may pass. Control of the direction of air flow is provided by pivoting the damper 100 about the axis 101 from positions which completely close the slots 102'to a position in which the slots 103 are covered. In the extreme portions of the range, ,air is respectively directed outwardly and upwardly atanangleof approximately 40 from the horizontal, and downward at an angle of 20j below" horizontal: Throughout" the intermediate por tions, the deflection of the air ranges between the lower angle position and the maximumupward deflection.

A separate automatic thermostat control may also be desired for turning off the apparatus upon the attainment ofa predetermined low temperature. As may be seen in Figure 7, this control'may comprise a conventional thermostatic switch 105 in the conductor 95 leading to the contact 91. Upon the lowering of the room temperature to a point at which'the thermostatic switch 105 is opened, the compressor will be temporarily shut down by deenergization of the motor 17. The unit 195 may be mounted in any convenient position and preferably is mounted for operation by means of a knob 106 at the end of the indicator-panel. 3

The indicator panel, with the control 'knob 50 and the control positions marked, may be uncovered, or on the other hand it may be hidden from view by a decorative bezel. This bezel may take the form shown in Figure 1 and 3 in which an arcuately contoured cover 106 is hinged as at 107 to the hood 36. A conventional biasing spring 108 may be provided for maintaining the bezel 106 snugly against the arcuate surface 109 of the hood 36 thereby completely covering the entire control panel except when pulled downwardly to expose the controls, as in Figures 1 and 3. The bezel 106 may, of course, be utilized to provide space for the manufacturers trade mark, or other similar informative or decorative material.

While the dampers 27 and 28 have been shown as rigid members, it is to be understood that flexible dampers are intended to be within the scope of the present invention. Thus, it is noted that each of the dampers 27 and 28 may be constructed of sheets of flexible vinyl plastic having a rigid plate secured to the central portion thereof. Using this material, the hinge may be completely eliminated and the edge of the vinyl secured to the partition 16. In operation the edge of the vinyl projecting beyond the edge of the rigid central panel will act as a resilient seal for the damper opening and the secured edge will also act as a satisfactory hinge.

It will thus be seen, that I have provided a complete control system for room air conditioners which is capable of actuation of substantially all of the elements controlling refrigeration, heating, and air flow distribution through a single, easily operable master control knob. Since, of course, numerous modifications and variations may be made without departing from the scope of the novel con cepts of the present invention it is therefore intended that the scope of the present invention be limited only by the appended claims.

I claim as my invention:

1. In a room air conditioning unit, an evaporator compartment and a condenser compartment, a first room air inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, an evaporator between said chambers and a fan between said evaporator and said second chamber for drawing air through said evaporator to said second chamber, first means for supplying outside air to said inlet chamber, second means for supplying air from said second chamber to said condenser compartment and a single reciprocating means for selectively actuating said first and second means, said reciprocating means comprising a first reciprocating element connected to said first means, a second reciprocating element connected to said second means, and a third reciprocating element slidably associated with said first and second reciprocating elements through oppositely acting lost motion connections.

2. Ina room air conditioning apparatus having evaporator and condenser compartments, a first room air inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, an evaporator between said chambers and a fan between said evaporator and said second chamber for drawingair through said evaporator and transmitting it to said second chamber under a first positive pressure, a second fan in said condenser compartment drawing air inwardly through a condenser into said condenser compartment under a second lower positive pressure, first damper means for supplying air from said condenser compartment to said inlet chamher, second damper'means for supplying air from said second chamber to said condenser compartment, biasing means urging both said first and second means into closed positions and a single reciprocating actuator for alternatively actuating said means into open positions.

'3. Ina room air conditioning apparatus having evaporator and condenser compartments, a first room air inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, an evaporator between said chambers and a fan between said evaporator and saidsecond chamber for drawing air through said evaporator to said second chamber, first means for supplying airfrom said condenser compartment to said inlet chamber, second means for supplying air from said second chamber to said condenser compartment, biasing means urging both said first and second means into closed positions and a single reciprocating actuator for alternatively actuating said means into open positions, said reciprocating actuator comprising a first reciprocating element connected to said first means, a second reciprocating element connected to said second means, and a third reciprocating element slidably connected to said first and second reciprocating elements through oppositely acting lost motion connections.

4. In a room air conditioning unit, an evaporator compartment and a condenser compartment, a first room air inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, an evaporator between said chambers and a fan between said evaporator and said second chamber for drawing air through said evaporator to said second chmber, first means for supplying outside air to said inlet chamber, second means for supplying air from said second chamber to said condenser compartment and a single reciprocating means for selectively actuating said first and second means, said reciprocating means comprising a first reciprocating elemerit connected to said first means, a second reciprocating element connected to said second means, and a third reciprocating element slidably associated with said first and second reciprocating'elements through oppositely acting lost motion connections, said third reciprocating element having a cam guide thereon associated with a fourth means for supplying room air to said room air inlet chamber, whereby said fourth means is controlled simultaneously with said first and second means.

5. In a room air conditioning apparatus having evaporator and condenser compartments, a first room air inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, an evaporator between said chambers and a fan between said evaporator and said second chamber for drawing air through said evaporator to said second chamber, first means for supplying air from said condenser compartment to said inlet chamber, second means for supplying air from said second chamber to said condenser compart ment, biasing means urging both said first and second means into closed positions and a single reciprocating actuator for alternatively actuating said means into open positions, said reciprocating actuator comprising a first reciprocating element connected to said first means, a second reciprocating element connected to said second means, and a thirdreciprocating element slidably connected to said first and second reciprocating elements through oppositely acting lost motion connections, said third reciprocating element having a cam guide thereon associated with a fourth means for supplying room air to said room air inlet chamber, whereby said fourth means is controlled simultaneously with said first and second means.

6. An air conditioner having a fresh air inlet damper,

a. pivoted room air inlet-damper, a room air exhaust damper, fan means for moving air through said dampers when said dampers are in selected open positions, a compressor for supplying refrigerant to cool the air moving through said room air inlet and said fresh air inlet dampers, and a master control for simultaneously operating said dampers, fan, and compressor, said control comprising a reciprocating element movable in a direction parallel to the pivot axis of the room air inlet damper and in said movement causing pivotal movement thereof to control its position, a switch controlling said fan and said compressor, means on said reciprocating element for actuating said switch, and a pair of reciprocating rods connecting said reciprocating element to said fresh air and exhaust dampers, said rod-s being alternatively actuated by said reciprocating element at the extreme ends of the .path of movement thereof.

7. An air conditioning apparatus comprising a housing having an evaporator compartment and a condenser compartment, a room air inlet chamber and a room air outlet chamber associated with said evaporator compartment an evaporator in said inlet chamber and extending substantially the full width of said apparatus, an evaporator fan between said evaporator and said second chamber, an outside air inlet associated with said condenser compartment and fan means associated with said condenser compartment for providing positive air pressure herein, a first damper connecting said outside air inlet to said room air inlet chamber, a second damper connecting said outside air inlet to said room air outlet chamber and a single reciprocating control for alternatively opening said dampers in opposite extreme positions against biasing means urging said dampers into closed position.

8. An air conditioning apparatus comprising a housing having an evaporator and condenser compartments, a room air inlet chamber and a room air outlet chamber associated with said evaporator compartment, and an outside air inlet to said condenser compartment, a first damper connecting said outside air inlet to said room air inlet chamber, a second damper connecting said outside air inlet to said room air outlet chamber, a third damper for varying the flow of air into the room air inlet chamber from a room and a single reciprocating control for alternatively opening said first and second dampers and simultaneously controlling the position of said third damper.

9. In an air conditioner, an air flow control damper having a pivotal axis intermediate its ends and a cam extending along one end in the direction of said axis, and reciprocating control means in sliding cooperating contact with said cam on said damper and movable along a path parallel to said axis for causing pivotal movement of said damper in response to variations in said cam.

10. In an air conditioner, an air flow control damper having a pivotal axis intermediate its ends, one of said ends having a cam edge associated therewith extending substantially a constant distance from said axis but having a varying lateral position relative to the plane of the other end, and reciprocating control means associated with said cam edge and movable along a path parallel to said axis for causing pivotal movement of said damper in response to the variations in lateral position of said cam edge relative to the plane of said other end.

11. An air conditioning apparatus comprising a housing having an evaporator and condenser compartments, a room air inlet chamber and a room air outlet chamber associated with said evaporator compartment, and an outside air inlet to said condenser compartment, a first damper connecting said outside air inlet to said room air inlet chamber, a second damper connecting said outside air inlet to said room air outlet chamber, a third damper for varying the flow of air into the room air inlet chamber from a room, a fourth damper controlling the direction of flow from said room air outlet chamber and having its pivot extending along the upper forward edge of said housing and having its damper surface selectively associated with air outlet apertures in the top and front surfaces of said housing and a single control for alternatively opening said first and second dampers and simultaneouslycontrolling,the'position ofsaid third damper.

12. In a room air conditioner, a room air circulation control comprising an air chamber containing conditionedair under-pressure, an opening in the top of said chamber adjacent a side wall thereof, an opening in the side-wall at a position adjacent said first opening and a damper pivotally mounted about an axis adjacent to and extending parallel to the-line of junction between said wall and said top for movement into postions variably apportioning the fiow of air through said openings, said damper extending substantiallythe entire width of said room air conditioner, said damper being of a size smaller than said opening whereby the flow of air may be directed as desired, said opening being only partially obstructed in any given position of adjustment.

13. In combination, a reciprocating control mechanism for simultaneously controlling a plurality of members each of which members is initially biased into a predetermined individual selected position comprising, a first reciprocating cable connected to one of said membersfor transmission vof force in opposition to its respective biasing force, a second reciprocating cable connected to a second of said members for the transmission of force thereto in opposition to its respective biasing force, a reciprocating bar, lost motion connection means on .said bar betweensaid bar and each of said cables whereby movement of said .bar from a neutral position in opposite directions will selectively reciprocate one only of said cables, andmeans for reciprocating said bar.

,14. In combination, a reciprocating control mechanism for simultaneously controlling a plurality of members each of which members is initially biased into a predetermined individual selected position comprsing, a first reciprocating cable connected to one of said members for transmission of force in opposition to its respective biasing force, a second reciprocating cable connected to a second of said members for the transmission of force thereto in opposition to its respective biasing force, a reciprocating bar, lost motion connection means on said bar between said bar and each of said cables whereby movement of said bar from a neutral position in opposite directions will selectively reciprocate one only of said cables, a third member pivotally mounted for pivotal movement about an axis parallel to the path of reciprocation of said bar, a cam edge on said third member projecting a distance from said pivotal axis substantially equal to the distance between said pivotal axis and said reciprocating bar, and cam follower means on said bar for cooperation with said cam whereby reciprocation of said bar causes rotation of said third member, and means for reciprocating said bar.

15. In an air conditioning apparatus, an evaporator compartment, a first room air inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, a third chamber between said first and second chambers, an evaporator between said first and third chambers, a centrifugal fan between said third chamber and said second chamber for drawing air through said evaporator into said tlrird chamber and thence through said fan into said second chamber under pressure, said fan having an axis of rotation substantially perpendicular to said evaporator and positioned eccentric thereof, the walls of said third chamber including a first perforate wall formed by said evaporator and a second wall lying in a plane between said evaporator and said fan, said second wall defining a plane lying at an acute angle to the plane of said evaporator and diverging therefrom in the direction of the center of the evaporator, said second wall having a short, generally circular, fan inlet duct therein leading to said fan, said duct having its central axis coaxial with said fan and terminating adjacent thereto.

16. In an air conditioning apparatus, an evaporator compartment, a first room inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, a third chamber between said first and second chambers, an evaporator between said first and third chambers, a centrifugal fan between said third chamber and said second chamber for drawing air through said evaporator into said third chamber and thence through said fan into said second chamber under pressure, said fan having an axis of rotation substantially perpendicular to said evaporator and positioned eccentric thereof, the walls of said third chamber including a first perforate wall formed by said evaporator and a second wall lying in a plane between said evaporator and said fan, said second wall defining a plane lying at an acute angle to the plane of said evaporator and diverging therefrom in the direction of the center of the evaporator, said second wall having a short, generally circular, fan inlet duct therein leading to said fan, said duct having its central axis coaxial with said fan and terminating adjacent thereto, and said second chamher having an opening at the top thereof expanding into a fourth chamber leading to said room.

17. In an air conditioning apparatus having an evaporator structure positioned in a first reference plane, a fan for drawing air through an inlet shroud inwardly along its axis and delivering it substantially peripherally,

said fan having its axis generally perpendicular to said plane and intersecting said evaporator at a point eccentric thereof, said shroud comprising a planar surface diverging away from said first plane in the direction of the center of said evaporator relative to said fan axis, and a fan inlet duct having an inlet faired into said planar surface and extending coaxially of said fan to an outlet parallel to said first plane and immediately adjacent to said fan whereby air is drawn evenly through said evaporator into said fan at an angle to the axis thereof.

18. In an air conditioning unit for enclosed rooms, an evaporator compartment and a condenser compartment, a first room air inlet chamber in said evaporator compartment, a second air outlet chamber in said evaporator compartment, an evaporator between said first room air inlet chamber and said second air outlet chamber, and a fan between said evaporator and said second chamber for drawing air through said evaporator to said second chamber under positive pressure, first means for supplying outside air at slightly lower positive pressure through said condenser compartment to said inlet chamber, second means for supplying air from said second chamber to said condenser compartment, and a. single reciprocating actuator for selectively actuating said first and second means.

References Cited in the file of this patent UNITED STATES PATENTS Eberhart Nov. 22, 

